In order to ensure and monitor the quality of service provided to end users of packet switched networks, including telecommunication networks, it is important to be able to measure properties of the link provided to endpoint devices (such as mobile telephones, laptop and desktop computers, and so forth) through one or more network interfaces between the respective endpoint device and the packet switched network. For example, it is desirable to measure data throughput, latency and loss, preferably in both the uplink and the downlink.
Many known techniques employ passive monitoring in the access network segment to measure throughput and loss. However, these techniques can be expensive, with costs which scale with packet rate. Furthermore, measurements of quality of service made within the access network segment may differ significantly from the actual quality of service received at endpoint devices.
It is also known to conduct active end-to-end tests in which software and hardware appliances function as endpoint devices, generating network traffic to simulate typical actions of users of the network and recording suitable metrics. However, end-to-end test apparatus can be expensive and cannot be practically employed to measure activity concurrently across more than a small proportion of network coverage. Furthermore, there is again a significant risk that measurements of quality of service made using end-to-end test apparatus differs significantly from the actual quality of service received by users of endpoint devices, or some subsets of users.
It is known to conduct passive tests at endpoint devices, for example, using the technique known as passive packet capture. Path flooding speed tests are also known for measuring link throughput. However, these tests are limited in their scope and generate a substantial amount of network traffic if they are to be reliable.
Accordingly, it is an object of the present invention to provide methods and apparatus for measuring properties of data transmission through packet switched networks to packet switched network endpoint devices, which provide measurements which are an accurate reflection of the quality of service received by users of the endpoint devices.
It is also an object of the present invention to provide methods and apparatus for measuring properties of data transmission through packet switched networks to packet switched network endpoint devices, which can be implemented in a cost-effective fashion without generating excessive network traffic, enabling large scale deployment.
Some embodiments of the invention aim to provide methods and apparatus which can be implemented using software applications which can be installed on endpoint devices, without the requirement for any specific hardware to be introduced into the access network segment.
Some embodiments of the invention aim to provide methods and apparatus which can provide measurements concerning properties of data transmission between endpoint devices and specific interfaces between network segments within a telecommunications network comprising at least one access network segment and at least one core network segment.